The prior art discloses straightforward latching arrangements, for example vacuum contactors. In these, a drive lever is pushed into the “off” switching position via a compression spring. In order for the switching device to be readily retained in the “on” switching position, the drive lever is latched, that is to say blocked, mechanically. For this purpose, a latch block is fastened on the drive lever. In the “on” switch position, the drive lever is blocked by a bolt. The bolt is a constituent part of a lever which is retained in the latched position via a spring and the resulting spring force. It is possible for the blocking unit comprising the bolt and lever to be pulled out of the latched position via a solenoid (triggering magnet) and the magnetic field thereof and thus to free the drive lever, or else the lever and the bolt are pulled mechanically out of the latched position via a rod in order to free the drive lever.
Such a system allows for only very low tolerances, so as to avoid undesired unlatching, that is to say unblocking, of the drive lever.
Even low tolerances result, in such a system, in high levels of friction, in particular between the latch block and bolt.
Overall, the known systems require high triggering forces, for example approximately 100 N in the embodiment described, for mechanical triggering, that is to say unlatching.
It is also the case that high forces are necessary for electromagnetic triggering, or unlatching, for which reason expensive special-production measures are required for the triggering magnets, in other words electromagnets. The high triggering forces necessitate a solid component construction and strong springs. It is also necessary for the lever of the latching arrangement to be welded on account of the high forces, and this results in high-outlay production.